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.\"	$NetBSD: mesg.1,v 1.3 1994/12/23 07:16:31 jtc Exp $
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.\"	@(#)mesg.1	8.1 (Berkeley) 6/6/93
.\"
.Dd $Mdocdate: September 3 2010 $
.Dt MESG 1
.Os
.Sh NAME
.Nm mesg
.Nd display (do not display) messages from other users
.Sh SYNOPSIS
.Nm mesg
.Op Cm n | Cm y
.Sh DESCRIPTION
The
.Nm mesg
utility is invoked by a user to control write access others
have to the terminal device associated with the standard error
output.
Write access is allowed by default, and programs such as
.Xr talk 1
and
.Xr write 1
may display messages on the terminal.
.Pp
The options are as follows:
.Bl -tag -width Ds
.It Cm n
Disallows messages.
.It Cm y
Permits messages to be displayed.
.El
.Pp
If no arguments are given,
.Nm mesg
displays the present message status to the standard error output.
.Sh FILES
.Bl -tag -width /dev/[pt]ty[pq]? -compact
.It Pa /dev/[pt]ty[pq]?
.El
.Sh EXIT STATUS
The
.Nm mesg
utility exits with one of the following values:
.Pp
.Bl -tag -width Ds -offset indent -compact
.It 0
Messages are allowed.
.It 1
Messages are not allowed.
.It \*(Gt1
An error has occurred.
.El
.Sh SEE ALSO
.Xr biff 1 ,
.Xr talk 1 ,
.Xr write 1
.Sh STANDARDS
The
.Nm
utility is compliant with the
.St -p1003.1-2008
specification.
.Sh HISTORY
A
.Nm mesg
command appeared in
.At v2 .
